а)<span>Ca, <span>Cu, N2, Н2, S8, O2 <span>Li3N </span></span></span>
<span><span>,) <span>CaC2 <span>Al2O3 <span> Al4C3 <span>Ca3N2 <span>CaF2 <span>PbO2 <span> Mg2Si
</span>в) Pb(NO3)2 <span> K2CO3 <span>Сa(NO3)2 <span>Mg3(PO4)2 <span>C3H7O2 </span><span>Al2(so4)3 <span>Na2CO3</span></span></span></span></span></span></span></span></span></span></span></span></span>
M(Si)=122*0.23=28 г n(Si)=28/28=1 атом
m(Na)=122*0.38=46 г n(Na)=46/23=2 атома
m(O)=122*0.39=48 г n(O)=48/16=3 атома
Na2SiO3
VNa=92/23·2=2mol-isbytok
vS=48/32=1.5mol
48g xg
2Na+S= Na2S
32g 78g
x=48·78/32=117g